Collection: Georgia Government Publications Title: Physiographic map of Georgia [1976] Creator: Clark, William Z
Zisa, Arnold C Contributor to Resource: Georgia. Department of Natural Resources. Geologic and Water Resources Division Publisher: Atlanta, Ga. : Georgia. Department of Natural Resources. Geologic and Water Resources Division Date of Original: 1976 Subject: Georgia Location: United States, Georgia, 32.75042, -83.50018 Medium: publications (documents) Type: Text Format: application/pdf Description: Map External Identifiers: Call Number GA N200.G3 M1 1976 P46 Metadata URL: https://dlg.galileo.usg.edu/id:dlg_ggpd_s-ga-bn200-pg3-bm1-b1976-bp46 Digital Object URL: https://dlg.galileo.usg.edu/do:dlg_ggpd_s-ga-bn200-pg3-bm1-b1976-bp46 Language: eng Holding Institution: University of Georgia. Map and Government Information Library Rights:
APPALACHIAN HIGHLANDS MAJOR DIVISION
APPALACHIAN PLATEAU PROVINCE
Southern Piedmont Section
Cumberland Plateau Section
Lookout Mountain District- The Lookout Mountain District is composed of t wo nearly f lat-topped mou ntains, Loo kout-P igeon and Sand Mou ntains, separated by Lookout Valley wh ich is a breached anticline. The mountains are capped by Rockcastle Sand stone of Pennsylvanian age, and t he valley is underla in by Chickamauga Limestone of Ordovician age. The upland slopes gentl y to the southwest from a maximum elevation of 2200 feet near Durham to an elevation of 2000 feet near the Alabama-Georgia border. The northwestern margi n of Lookout Mountain and t h e southeast ern m argin of Sand Mountai n are marked by a conti nuous escarpment that drops abruptly 1000. 1 200 feet to Lookout Valley. Elevatio ns in Lookout Valley vary from 800-1000 feet . The escarpment on the southeastern side of Lookout- Piegon Mountain, the d istrict and province boundary, drops abrupt ly 8001000 feet to the Chicka mauga Valley D istrict. These escarpments are breached by numerous small streams which have their source on top of the u p land and reach the valleys through deep notches in t he cliffs.
RIDGE AND VALLEY PROVINCE
Southern Valley and Ridge Section
Chickamauga Valley District- The Chickamauga Valley Distr ict is characterized by a series of gently rolling, discon t inuous, northeast-trending valleys interrupted by low, linear, parallel ridges. The valley f loors a re predominantly limestone and dolomite of Cambro Ordovician age whi le the ridges are capped by the more resistant cherty units of the Knox Group, also of Cambro-Ordovician age. The ridge tops are approximately 1000 feet in e levation and stand 200300 feet above the intervening valleys. Rectangular drainage patterns in this d istrict are indicative of structu ra l control.
Armuchee Ridges District -A series of prominent, narrow, chev ro n-shaped ridges dominate the Armuchee Ridges District. These ridges rise abruptly 600-700 feet a bove the Chickamauga Valley D is t rict to the northwest and the Great Valley District to the south and east. The southern and eastern boundary c lose ly parallels the Rome Fau lt. These ridges, capped predominantly by the Red Mountain san d stone of S ilurian age, stand at e levations of 1400-1600 feet. Intervening va lley floors are generally underlain by shales and limestones of Mississippian and Cambro-Ordovician age, respectively.
The Great Valley District- The Great Valley District is typically broad and open wi t h a f ew scattered ridges and hills. E levations throughout t he area range from 700800 feet above sea level w ith relief of 50 to 100 feet. The floor of the valley is u nde rlain by shales, dol omites and limestones of Cambrian a n d Ordovician a ge. The eastern boundary of the Great Val ley follows the escarpment of the Great Smoky-Cartersville Fault.
BLUE RIDGE PROVINCE
Southern Blue Ridge Section
Cohutta Mountains D istrict- An irregular mass of rugged mountains ranging in elevation f rom 3000-4000 feet is characteristic of the Cohutta Mou n tains District . E rosion of metamorphosed sedi ments of t h e Ocoee ser ies by t he headwater tributaries of south westward and northward flowing streams has produced valleys 1000.1500 feet below the mountain crests. The sou t hern boundary o f this district slopes steeply to the lower e levations o f the Chero kee Uplands District. In Georgia the Cohutta Mountains are sepa rated from the main body of the Blue Ridge by the McCaysville Basin and t he Jasper Ridges.
McCaysville Basin District - Mountains almost completely enc lose the McCaysvil le Basin District and rise from the 2000 foot elevation at the edge of the basin to heights of 40004500 feet above sea level. This topograph ic basi n is bisected by t h e northeasttrending J asper Ridges; however, the topography o n both sides of these ridges is remarkably similar. The gently rolling topography, produced by erosion of the Great S m oky Group, varies in elevation f r om 1600 to 1800 feet. Rel ief throughout the Basin varies from 200-300 feet except along the nort hwest-flowing stream valleys and nea r t he Jasper R idges where it ranges from 300-500 feet.
Blue Ridge Mountains District - A mass of rugged mountains and ridges ranging in elevation from 3500-4700 feet in the north and east to 3000-3500 feet in the southwest is the dom inant topo graph ic feature of the Blue Ridge Mountains District. Differing rates of erosion upon t he Great Smoky Grou p b y t he headwater tributary streams, that eventually drain to either the Atlantic Ocean or the Gu lf of Mexico, have p roduced valleys that are 1500-2000 feet below the adjacent summits. The southern boundary of the Blue Ridge abut s the Piedmont Province at approximately the 1700 f oot elevation where a sharp chan ge in regional slope occurs.
Upland Georgia Subsection
!chu\ Cherokee Upland District- The northern portion o f the Chero kee U p la n d District is a rough, h illy surface with e levatio ns rang ing from 1300-1500 feet. Except for a few isolated mountains, elevat ions gradually decrease to 1000 f eet in the southern p art. T he westward-fl owi ng streams in the northern area occupy deep, narrow valleys 300-600 feet below the surrounding su rface, wh il e t he southwestward flowing streams in t he southern portion have wider, m ore open valleys 200-300 feet below t h e adjacent ridges. T he eastern a nd southern boundaries are formed by the low, linear, parallel r idges of the Hightower-Jasper R idges District.
Dahlonega Upl and Distr ict - T he rough and hilly nort heastern part o f the Dahlonega Upland Dist rict stands 1500 1700 feet above sea level. Streams in t his area flow south o ut of the Blue Ridge Mountains District, and have cut deep, narrow valleys 500600 feet below the surrounding surface. In t he southern and so uthwes tern portions, surface elevations decrease t o 1200 feet. Stream valleys are wider, more open , and o nl y 200-300 feet below the adjacent surface. The southern and western boundaries are f ormed by the low linear, parallel r idges of the Hightower-Jasper Ridges District.
Hightower-Jasper Ridges District - Although t h e Hightower Ridges and Jasper Ridges have d iff erent struct ural and litho logic histories, they are topographic ally so similar that they may be discussed together. The HightowerJasper Ridges District consists of a series of low, linear, parallel ridges separated by narrow valleys. The Hightower Ridges range in elevati on from 1500 feet in the northeast to 1000 feet in the southwest. Relief in th is area varies from 500 feet in the north east to 200 feet in the sou t hwest. The Jasper R idges bisect the McCaysville Basin Distric t and continue southward as a low area between the Cohutta and Blu e Ridge Mount ains. These ridges range in elevation fro m 2400 feet in the no rth to 1200 feet near Canton where they join the Hightower Rid ges. Relief varies from 800 feet in t h e north to 200 feet near La ke Allat oona. Some structural con trol of stream s in t he d ist rict is ex h ib ited by the mod i fied rectangular drainage patterns. The southe r n a n d west ern bou ndaries are locat ed w here there is a decrease in the d ensity of the linear ridges.
Central Uplands District - The n ortheastern an d central por tio ns of the Central Upland District are a series of low, linear r idges, 13001 500 feet above sea level, and separated by broad, open valleys. Streams flow ing through this section are generall y transverse t o the structu re and occupy va lleys 150200 feet below t he ridge crests. In the southwestern part, elevations decrease to 1100 f eet, and the linearity of the topography is n o t so apparent. Stream valleys in t he southwestern portion are not as open as those to the northeast. They exh ibit a rectangu lar drainage pattern a nd lie only 100 150 feet below t he surrounding area. The southern boundary of th is district is the ridge crest that m a r ks the begi n ning of the Gainesv ille Ridges Dist rict.
Gainesville Ridges Distri ct - A series of northeast-trending, low, linear, parallel r idges separated by narrow valleys characterizes the Gainesville Ridges District. The ridges are composed of quartzite and gneiss, while the vall eys are u n derlain by phyllonite and schist. These r idges vary in e levation from 1500-1600 f eet in the northeast and decrease gradu ally to 700 feet in the s outhwest. Relief varies f rom 100 200 feet in the northeast to 70-100 feet in the southwest. The courses o f the Chattahoochee River and it s tributaries are strongly controlled by the ridges in this d ist rict and exh ib it a good example of rectangular d rainage. The southern boundary follows a ridge th at is continuous throughout most of its ext ent, dec reasing in e levation from 1 100 feet in the northeast to 700 feet in the southwest. This ridge c rest is the drainage d ivide bet ween southwest f lowing streams and t hose streams drain ing to the south .
Midland Georgia Subsection
W inder Slope D istrict- The gent ly rolling topography of the Wi nder Slope District s lopes gradu a lly from an elevation of 1000 feet in the north to 700 feet at the southern edge. This district is dissected by the headwater tributaries of the major streams draining to the Atlantic Ocean. Numerous dome-shaped, granitic mountains are located on the interfluves in the s outher n and western portion of this distr ict. The stream valleys wh ich are fa ir ly deep and narrow, lie 100200 feet be low the narrow, ro u nded stream divides. The western boundary f ollows t he drain age d ivide that separat es streams d raining to the A tl antic Ocean from t hose drai n ing to the Gu lf of Mex ico. Th e southern boundary approximates t h e 700 foot elevation wher e a sharp b reak in regional slope occurs.
T E N N 8~E S S E E
PHYSIOGRAPHIC MAP
OF GEORGIA
by
William Z. Clark, Jr. and Arnold C. Zisa
D EPARTME NT OF NA T URAL RESOURCES Joe D. Tanner, Commissioner
T H E GEOLOG IC A N D WA T ER RESO U RCES DI VI S IO N Sam M. Pic ker ing, State Ge o lo gis t a n d Division D ir ec tor
Atlanta
1976
Reprinted 1988 by the Geologic S u rvey Branch
of the Environ m ental Protection D iv ision of the Georg ia Departmen t of Natural Resources